Well compressing a video in a archive like .tar, .rar, .7z etc will make no meaningful change to the file size. Re-encoding the video to something still worth watching is unlikely to get you to the size you are after which is over a 50%+ reduction.
Spanned zip / rar would work but it would require multiple emails to send the pieces and is just overly complicated for the average person to deal with.
All I can say is google drive allows you to share selected content, to anyone who has the link for it thus no inviting is required. Other than that I have no good answer for your scenario as you've ruled it all out.